Can anyone explain why the large tapioca pearls in boba tea are black? Are they different from regular tapioca, cooked differently, ...?
I was shopping in the International District in Seattle yesterday and did find some quite large white (dry) tapioca pearls, but when I soaked them, they totally disintegrated (I guess 49 cents was too good to be true). One store also carried cryovac bags of 'pre-cooked, needs only five minutes cooking' large black tapioca pearls (covered with a powdery substance to keep them from sticking), but I didn't want to spend $10 on them. There were also some light green (dry) balls, but they seemed to only come in small.
Any clues as to what the tea shops do? I want the large pearls to add texture to a (dessert) fruit soup I'm making.